JP2016191903A - Pixel structure and display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pixel structure that can improve stability of liquid crystal alignment and solve the problem of leakage of light in a dark condition, and a display panel that has good transmittance.SOLUTION: A pixel structure comprises a substrate, opposing substrate, scan line and data line, active component, pixel electrode, and protective layer. The pixel electrode includes at least one block-like electrode and a plurality of first branch electrodes. The protective layer includes at least one block-like projection pattern, a plurality of branch projection patterns, and a plurality of concave grooves. The first branch electrodes are provided on the block-like projection patterns. An orthogonal projection edge of the block-like electrode and an orthogonal projection edge of the first branch electrode closest to that of the block-like electrode have a gap width W1, and satisfies the relationship 0 μm<W1≤4 μm. The orthogonal projection edge of the block-like electrode and an orthogonal projection edge of the block-like projection pattern have a distance W2, and satisfies the relationship 2 μm≤W2≤5.5 μm.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a pixel structure and a display panel.

  As flat panel displays, liquid crystal displays (LCDs) are widely used. The liquid crystal display has a display panel composed of two substrates. In a liquid crystal display, an electric field generating electrode such as a pixel electrode or a common electrode is formed on a substrate, a liquid crystal layer is provided between two substrates, and an electric field is generated by applying a voltage to the electric field generating electrode. Generated. Depending on the generated electric field, the orientation of liquid crystal molecules in the liquid crystal layer and the polarization of incident light are determined, and an image can be displayed.

  Among liquid crystal displays, a liquid crystal display in a VA (vertical alignment) mode has attracted a great deal of interest because of its high contrast and wide viewing angle. Specifically, in a VA mode liquid crystal display, when an electric field is not applied, the main axis (long axis) of the liquid crystal molecules is perpendicular to the alignment direction of the display panel. In particular, in a VA mode liquid crystal display, by simply forming a cut (for example, a slit) in one pixel electrode, a plurality of regions including liquid crystal molecules having different orientations are formed in one pixel electrode, and a wide field of view is obtained. A corner can be realized.

Taiwan Patent Application Publication No. 201508400 Specification US Patent Application Publication No. 201302242239 US Patent Application Publication No. 201110260957

  However, when a plurality of branch electrodes are formed by forming a cut in the pixel electrode described above, the liquid crystal molecules in the electric field generating electrode at the cut are slightly twisted or not stably tilted. Efficiency is reduced, and the transmittance is also reduced. In addition, the liquid crystal molecules tilted in an unstable manner cause light leakage in the dark state. Incidentally, the pixel electrode has only a plurality of branch electrodes, but does not have any other pattern or shape design. Note that the protective layer for isolating the pixel electrode and the transistor is provided with only a contact hole for communicating the pixel electrode and the transistor, and does not have any other pattern or shape design.

  Note that this background information is provided to clarify information that the applicant may have related to the present invention. None of the information described so far constitutes prior art to the present invention and should not be considered as such.

  An object of the present invention is to provide a pixel structure capable of improving the stability of liquid crystal alignment and solving the problem of light leakage in a dark state.

  Another object of the present invention is to provide a display panel having good transmittance.

  The pixel structure according to the present invention includes a substrate, a counter substrate, a scanning line and a data line, an active element, a pixel electrode, and a protective layer. The counter substrate is disposed above the substrate, and the common electrode is disposed on the side facing the substrate. Scan lines and data lines are formed on the substrate. The active element is formed on the substrate and connected to the scanning line and the data line. The pixel electrode is electrically connected to the active element, and includes at least one block-shaped electrode and a plurality of first branched electrodes. The protective layer is provided below the pixel electrode and includes at least one block-shaped projection pattern and a plurality of branched projection patterns. The block electrode of the pixel electrode is provided so as to cover the plurality of branch projection patterns of the protective layer in a conformal manner and project by the plurality of branch projection patterns to form a plurality of second branch electrodes. The plurality of first branch electrodes of the pixel electrode are provided on the block-shaped protrusion pattern of the protective layer, and the edge of the block-shaped electrode of the pixel electrode extends to the block-shaped protrusion pattern of the protective layer. A gap width W1 (0 μm <W1 ≦ 4 μm) is provided between the orthogonal projection edge of the block-shaped electrode and the orthogonal projection edge of the first first branch electrode that is the closest. There is a distance W2 (2 μm ≦ W2 ≦ 5.5 μm) between the orthogonal projection edge of the block-shaped electrode and the orthogonal projection edge of the block-shaped protrusion pattern.

  A display panel according to the present invention includes a plurality of the pixel structures, and a pixel cell is configured by at least three pixel structures, and a width or interval of a plurality of first branch electrodes of at least one pixel structure in the pixel cell is a pixel cell. The width or interval of the plurality of first branch electrodes of other pixel structures in FIG.

  Another pixel structure according to the present invention includes a substrate, a counter substrate, a scanning line and a data line, an active element, a pixel electrode, and a protective layer. The counter substrate is disposed above the substrate, and the common electrode is disposed on the side facing the substrate. Scan lines and data lines are formed on the substrate. The active element is formed on the substrate and connected to the scanning line and the data line. The pixel electrode is electrically connected to the active element and has a plurality of branch electrodes. When there is a gap between two adjacent branch electrodes and the distance of the slit is a, the relationship 0 μm <a ≦ 3 μm is satisfied. The protective layer is provided below the pixel electrode and has a plurality of branching protrusion patterns. At least one groove is provided between two adjacent branching protrusion patterns. Each branch electrode of the pixel electrode is disposed corresponding to one groove of the protective layer. The branch electrode extends from the groove to the adjacent branch projection patterns on both sides, and is arranged so that the gap overlaps the branch projection pattern. When the distance between the orthogonal projection edge of the branch electrode and the orthogonal projection edge of the groove is b, the relationship of 1.5 μm ≦ b ≦ 10 μm is satisfied.

  Another display panel according to the present invention includes a plurality of the other pixel structures, wherein a pixel cell is configured by at least three pixel structures, and the width or interval of the plurality of first branch electrodes of the at least one pixel structure in the pixel cell. However, the width or interval of the plurality of first branch electrodes of other pixel structures in the pixel cell is different.

  As described above, the pixel electrode has a plurality of branch electrodes, and the protective layer has a plurality of branch protrusion patterns. The pixel electrode according to the present invention can have a desired concavo-convex structure (a structure projecting upward and recessed downward) by arranging the branch electrode and the branch projection pattern to intersect each other. Thereby, the problem that the inclination of the liquid crystal becomes unstable due to insufficient depth of the concave groove in the protective layer can be prevented. In addition, the pixel structure according to the present invention can reduce light leakage in the dark state due to the inclined side wall of the branch protrusion pattern of the protective layer, and a display panel having good transmittance can be obtained.

  The above and other aspects of embodiments of the present invention will become more apparent from the description of the preferred embodiments with reference to the following drawings.

It is a schematic sectional drawing which shows the display panel which concerns on one Embodiment of this invention. It is a schematic top view which shows the pixel array layer concerning one Embodiment of this invention. 1 is a schematic top view illustrating a pixel electrode having a pixel structure according to a first embodiment of the present invention. FIG. 4 is a schematic top view showing a protective layer provided below the pixel electrode in FIG. 3. FIG. 5 is a schematic view showing that the pixel electrode of FIG. 3 and the protective layer of FIG. 4 overlap. FIG. 6 is a schematic enlarged view showing a K1 region in FIG. 5. FIG. 6 is a schematic sectional view taken along line I-I ′ in FIG. 5. FIG. 6 is a schematic cross-sectional view showing a pixel structure taken along line I-I ′ in FIG. 5 according to another embodiment of the present invention. It is a schematic top view which shows the pixel electrode of the pixel structure which concerns on 2nd Example of this invention. FIG. 10 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. 9. It is the schematic which shows that the pixel electrode of FIG. 9 and the protective layer of FIG. 10 have overlapped. It is a schematic enlarged view which shows K2 area | region of FIG. It is a schematic top view which shows the pixel electrode of the pixel structure which concerns on 3rd Example of this invention. It is a schematic top view which shows the protective layer provided under the pixel electrode of FIG. FIG. 15 is a schematic diagram showing that the pixel electrode of FIG. 13 and the protective layer of FIG. 14 overlap. It is a schematic enlarged view which shows K3 area | region of FIG. It is a schematic top view which shows the pixel electrode of the pixel structure which concerns on 4th Example of this invention. FIG. 18 is a schematic top view showing a protective layer provided below the pixel electrode in FIG. 17. FIG. 19 is a schematic diagram showing that the pixel electrode of FIG. 17 and the protective layer of FIG. 18 overlap. It is a schematic enlarged view which shows K4 area | region of FIG. It is a schematic top view which shows the pixel electrode of the pixel structure which concerns on 5th Example of this invention. It is a schematic top view which shows the protective layer provided under the pixel electrode of FIG. FIG. 23 is a schematic diagram showing that the pixel electrode of FIG. 21 and the protective layer of FIG. 22 overlap. It is a schematic enlarged view which shows K5 area | region of FIG. It is a schematic top view which shows the pixel electrode of the pixel structure which concerns on 6th Example of this invention. FIG. 26 is a schematic top view showing a protective layer provided below the pixel electrode in FIG. 25. FIG. 27 is a schematic diagram showing that the pixel electrode of FIG. 25 and the protective layer of FIG. 26 overlap. It is a schematic enlarged view which shows K6 area | region of FIG. FIG. 28 is a schematic sectional view taken along line J-J ′ in FIG. 27. It is a schematic top view which shows the pixel electrode of the pixel structure which concerns on 7th Example of this invention. FIG. 31 is a schematic top view showing a protective layer provided below the pixel electrode in FIG. 30. FIG. 32 is a schematic diagram showing that the pixel electrode of FIG. 30 and the protective layer of FIG. 31 overlap. FIG. 33 is a schematic enlarged view showing a K7 region in FIG. 32. It is a schematic top view which shows the pixel electrode of the pixel structure which concerns on 8th Example of this invention. FIG. 35 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. 34. FIG. 36 is a schematic diagram showing that the pixel electrode of FIG. 34 and the protective layer of FIG. 35 overlap. FIG. 37 is a schematic enlarged view showing a K8 region in FIG. 36. FIG. 3 is a schematic diagram illustrating a relationship between the transmittance of the display panel and the pixel structure according to the first embodiment of the present invention. It is the schematic which shows the relationship between the transmittance | permeability of the display panel which concerns on a comparative example, and pixel structure. It is the schematic which shows the relationship between the transmittance | permeability of the display panel which concerns on 1st Example of this invention, and W1. It is the schematic which shows the relationship between the transmittance | permeability of the display panel which concerns on 1st Example of this invention, and W2. It is the schematic which shows the relationship between the transmittance | permeability of the display panel which concerns on 6th Example of this invention, and a and b. It is the schematic which shows the relationship between the transmittance | permeability of the display panel which concerns on 6th Example of this invention, and mask shift distance. FIG. 28 is another schematic cross-sectional view along the line J-J ′ in FIG. 27.

  FIG. 1 is a schematic cross-sectional view showing a display panel 1000 according to an embodiment of the present invention. As shown in FIG. 1, the display panel 1000 of this embodiment includes a substrate 10, a counter substrate 20, a display medium 30, and a pixel array layer 12. In the present invention, the display panel 1000 is, for example, a liquid crystal display panel.

  The material of the substrate 10 includes glass, quartz, organic polymer, or other similar materials.

  The counter substrate 20 is disposed to face the substrate 10. Examples of the material of the counter substrate 20 include glass, quartz, organic polymer, and other similar materials. In the counter substrate 20, a common electrode 22 is disposed on the side facing the substrate 10. Examples of the material of the common electrode 22 include indium tin oxide (ITO), indium zinc oxide (IZO), aluminum tin oxide (ATO), aluminum zinc oxide (AZO), and indium germanium zinc oxide (IGZO). It may be a metal oxide, graphene, carbon nanotube, other suitable material, or a layer in which at least two of these materials are stacked.

  The display medium 30 is disposed between the substrate 10 and the counter substrate 20. The display medium 30 includes a plurality of liquid crystal molecules (not shown). The display panel 1000 of this embodiment includes not only liquid crystal molecules in the display medium 30 but also a monomer compound. In other words, the display medium 30 includes liquid crystal molecules and monomer compounds before the monomer compound curing process is performed in the display panel 1000. When the monomer compound curing process is performed in the display panel 1000, the monomer compound is polymerized so that a polymer thin film is formed on the surface of the pixel array layer 12. The polymer thin film may be called an alignment film because it can align liquid crystal molecules. The curing process may be a photopolymerization method, a thermal polymerization method, or a combination thereof. Depending on the curing process, a voltage may be applied so as to generate a retilt angle in the liquid crystal molecules. As described above, the display medium 30 is mainly composed of liquid crystal molecules after the monomer compound curing process is performed in the display panel 1000.

  The pixel array layer 12 is disposed on the substrate 10 and the display medium 30 is covered thereabove. The pixel array layer 12 is composed of a plurality of pixel structures 100. The design of the pixel structure 100 will be described in detail with reference to FIG. FIG. 2 is a schematic top view showing the pixel array layer 12 according to an embodiment of the present invention. For convenience of explanation, only the 3 × 3 pixel structure 100 of the pixel array layer 12 is shown in FIG. However, it should be understood by those skilled in the art that the pixel array layer 12 shown in FIG. 1 is composed of a plurality of pixel structures 100 that are actually arranged in an array.

  As shown in FIG. 2, the pixel structure 100 includes a scanning line SL, a data line DL, an active element T, a pixel electrode PE, and a protective layer (not shown).

  The extending direction of the scanning line SL is different from the extending direction of the data line DL. Preferably, the extending directions of the data lines DL and the scanning lines SL are orthogonal to each other, but the present invention is not limited to this. Further, the scanning lines SL and the data lines DL are arranged in different film layers, and an insulating layer (not shown) is sandwiched therebetween. The scanning lines SL and data lines DL are used to transmit driving signals (for example, scanning signals and data signals) of the pixel structure 100. In general, the scanning lines SL and the data lines DL are made of a metal material, but are not limited thereto. In other embodiments of the present invention, the materials of the scan lines SL and data lines DL may be alloys, metal oxides, metal nitrides, metal oxynitrides, graphene, carbon nanotubes, other suitable conductive materials, or these It may be a layer in which at least two materials are laminated.

  The active element T is electrically connected to the scanning line SL and the data line DL. Here, the active element T is, for example, a thin film transistor (TFT) including a gate, a channel layer, a drain, and a source. The gate is electrically connected to the scanning line SL, and the source is electrically connected to the data line DL. In other words, when the control signal is input to the scanning line SL, the scanning line SL and the gate are electrically connected, and when the control signal is input to the data line DL, between the data line DL and the source. Are electrically conducted. The channel layer is disposed above the gate and below the source and drain. In the present embodiment, the active element T may be, for example, a bottom gate TFT, but is not limited thereto. In another embodiment, the active element T may be a top gate type TFT in which a channel layer is disposed below the gate and below the source and drain. The material of the channel layer is polysilicon, microcrystalline silicon, single crystal silicon, amorphous silicon, metal oxide semiconductor material, organic semiconductor material, graphene, carbon nanotube, other suitable conductive material, or at least of these materials The layer which laminated | stacked two may be sufficient.

  The pixel electrode PE is electrically connected to the active element T. For example, the pixel electrode PE can be electrically connected to the drain of the active element T through a contact window (not labeled). The pixel electrode PE is, for example, a metal oxide such as indium tin oxide, indium zinc oxide, aluminum tin oxide, aluminum zinc oxide, indium germanium zinc oxide, graphene, carbon nanotube, other suitable materials, or these It may be a layer in which at least two materials are laminated.

  The protective layer is disposed below the pixel electrode PE. The material of the protective layer may be, for example, an inorganic material, an organic material, a single mixed layer or a laminate of these materials. Inorganic materials include silicon oxide, silicon nitride, silicon oxynitride, graphene nitride, graphene oxide, graphene oxynitride, carbon nitride nanotubes, carbon oxide carbon nanotubes, carbon oxynitride carbon nanotubes, and other suitable materials It may be a material or a layer in which at least two of these materials are laminated. Examples of the organic material include a colorless photoresist, a transparent color photoresist, benzocyclobutene (BCB), polyimide (PI), polymethacrylate (PMA), and other suitable materials, or these materials. The layer which laminated | stacked at least 2 of these may be sufficient.

  In the liquid crystal display panel of the present invention, a pixel structure having an uneven structure is required. In order to satisfy the above requirements, the pixel electrode PE and the protective layer in the pixel structure of the present invention are designed in different ways. Hereinafter, pixel structures according to some embodiments of the present invention will be described in detail with reference to the drawings. Thus, the design of the pixel electrode PE and the protective layer in the pixel structure can be clarified.

FIG. 3 is a schematic top view showing a pixel electrode having a pixel structure according to the first embodiment of the present invention. FIG. 4 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 5 is a schematic diagram showing that the pixel electrode of FIG. 3 and the protective layer of FIG. 4 overlap.
As shown in FIG. 3, the pixel electrode 120 includes at least one block electrode (also referred to as a plate electrode) 122 and a plurality of first branch electrodes 124. Specifically, the block electrode 122 is an unpatterned electrode region in the pixel electrode 120. That is, the block electrode 122 does not have any opening, hole, slit, groove, or gap. On the other hand, the first branch electrode 124 is a patterned electrode region in the pixel electrode 120. The pixel electrode 120 may further include a main electrode 126. The plurality of first branch electrodes 124 are connected to the main electrode 126, and slits (symbols) are provided between the two adjacent first branch electrodes 124 and between the main electrode 126 and the adjacent first branch electrode 124. Is not attached).
In this embodiment, as an example, the two block electrodes 122 are arranged on both sides of the main electrode 126. That is, the first branch electrode 124 and the main electrode 126 are disposed between the two block electrodes 122 so that the two block electrodes 122 do not directly contact each other, but the present invention is not limited to this. In another embodiment, the pixel electrode 120 may include one block electrode 122, a plurality of first branch electrodes 124, and a main electrode 126. The orthogonal projection shape (to the substrate) of the block-shaped electrode 122 of the present invention has a polygonal shape, and in the present embodiment, has a pentagonal shape as an example, but is not limited thereto. As described above, various shapes such as a rectangular shape or a zigzag shape can be formed according to the contour shape of the orthogonal projection (to the substrate) of the first branch electrode 124 and the block electrode 122. It is not limited.

As shown in FIG. 4, the protective layer 140 has at least one block-like protrusion pattern 142 and a plurality of branch protrusion patterns 144. Further, a concave groove 145 is provided between the branching protrusion patterns 144. Specifically, the block-like protrusion pattern (also referred to as a plate-like protrusion pattern) 142 occupies a considerably large area in the protective layer 140 and is an unpatterned protrusion region. That is, the block-shaped protrusion pattern 142 does not have any opening, hole, slit, concave groove, or gap. A portion where the branching protrusion pattern 144 and the concave groove 145 are formed is a region having an uneven structure in the protective layer 140.
In this embodiment, the protective layer 140 has a main projection pattern 146 connected to the plurality of branch projection patterns 144. A concave groove 145 is provided between two adjacent branching protrusion patterns 144 and between the main protrusion pattern 146 and the adjacent branching protrusion pattern 144. In the present embodiment, the block-shaped protrusion pattern 142 is disposed between the branch protrusion patterns 144 in the two separate areas so that the branch protrusion patterns 144 in the two separate areas do not directly contact each other. . In this manner, the branching protrusion patterns 144 in the two separate areas each have the main protrusion pattern 146, and the main protrusion patterns 146 in the two separate areas do not directly contact and connect to each other, and the block-like protrusion pattern Although it is connected via 142, it is not limited to this. In another embodiment, the protective layer 140 may include two block-shaped protrusion patterns 142, branch protrusion patterns 144 in a plurality of regions, and a main protrusion pattern 146.

  FIG. 5 is a schematic diagram showing that the pixel electrode 120 of FIG. 3 and the protective layer 140 of FIG. 4 overlap. 3 to 5 together, the pixel electrode 120 is formed above the protective layer 140, and the block-like electrode 122 of the pixel electrode 120 conformally on the plurality of branching protrusion patterns 144 of the protective layer 140. Covering, projecting with a plurality of branch projection patterns 144, recessed with a plurality of concave grooves 145, and provided with a plurality of second branch electrodes 128. The main electrode 126 and the first branch electrode 124 of the pixel electrode 120 are formed on the block-shaped protrusion pattern 142 of the protective layer 140. The main electrode 126 of the pixel electrode 120 may be disposed to intersect with the main protrusion pattern 146 of the protective layer 140, but is not limited thereto. The main electrode 126 and the main protrusion pattern 146 are preferably orthogonal to each other as shown in FIG. Incidentally, the main electrode 126 of the pixel electrode 120 includes electrodes arranged in two intersecting directions, for example, the row direction and the column direction. Either one of the two directions is substantially parallel to the main protrusion pattern 146 and the other substantially intersects the main protrusion pattern 146 (eg, substantially perpendicular).

  FIG. 6 is a schematic enlarged view showing the K1 region of FIG. FIG. 7 is a schematic cross-sectional view along the line I-I ′ in FIG. 5. Please refer to FIG. 5, FIG. 6 and FIG. The width L1 of the branching protrusion pattern 144 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S1 between the branching projection patterns 144 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S <b> 1 can be regarded as the width of the concave groove 145. The width L2 of the first branch electrode 124 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S2 between the first branch electrodes 124 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S2 can be regarded as the width of the slit (not labeled). Thus, by adjusting the widths L1 and L2 and the intervals S1 and S2, the tilt direction of the liquid crystal molecules can be finely adjusted so that disclination does not occur.

  Specifically, the edge 122 e of the block electrode 122 of the pixel electrode 120 further extends onto the block protrusion pattern 142 of the protective layer 140. There is a gap width W1 between the orthogonal projection edge 122e (to the substrate) of the block electrode 122 and the orthogonal projection edge 124e (to the substrate) of the first first branch electrode 124a closest to the block electrode 122. Considering the transmittance, the gap width W1 satisfies the relationship of 0 μm <W1 ≦ 4 μm, preferably satisfies the relationship of 1 μm ≦ W1 ≦ 3 μm, and is most preferably about 2 μm. A distance W2 is provided between the orthogonal projection edge 122e of the block-like electrode 122 and the orthogonal projection edge 142e (to the substrate) of the block-like projection pattern 142. Considering the transmittance, the distance W2 satisfies the relationship of 2 μm ≦ W2 ≦ 5.5 μm, and is most preferably about 3 μm.

  As shown in FIG. 7, the edge 122 e of the block electrode 122 of the pixel electrode 120 extends to the block protrusion pattern 142 of the protective layer 140. Specifically, the boundary between the block electrode 122 and the first first branch electrode 124 a is not provided in the groove 145 of the branch protrusion pattern 144 of the protective layer 140, and the block protrusion pattern of the protective layer 140 is not provided. It is formed so as to be provided in the protruding region of 142. In the present embodiment, each depth d of the concave groove 145 of the branching protrusion pattern 144 satisfies a relationship of 0.1 μm ≦ d ≦ 0.3 μm, for example, but is not limited thereto.

  In particular, the boundary between the block-shaped electrode 122 having the pixel structure and the first first branch electrode 124 a is provided on the block-shaped protrusion pattern 142 of the protective layer 140. According to the pixel structure of the present embodiment, it is possible to improve the efficiency of the liquid crystal corresponding to the W2 junction (that is, the portion where the block-shaped electrode 122 and the block-shaped protrusion pattern 142 overlap in plan view). In addition, in the pixel structure formed by the branching protrusion pattern 144 and the concave groove 145 of the protective layer 140, a light leakage in a dark state caused by an inclined side wall (taper) can be reduced, and the display panel has good transmittance. Can be obtained.

  FIG. 8 is a schematic cross-sectional view showing a pixel structure taken along line I-I ′ in FIG. 5 according to another embodiment of the present invention. Since the embodiment shown in FIG. 8 is similar to the embodiment shown in FIGS. 5 to 7, the same or similar elements are denoted by the same or similar reference numerals, and redundant description is omitted. As shown in FIG. 8, a color filter layer 160 may be further disposed below the pixel electrode 120 in addition to the protective layer 140. As the protective layer 140, an inorganic material, an organic material, or a layer in which the above materials are stacked may be used. In order to reduce interference with the color of the color filter layer 160, the organic material of the protective layer 140 is not preferably selected from color resists. Here, the color filter layer 160 is composed of, for example, at least one of a green filter layer, a blue filter layer, and a red filter layer.

FIG. 9 is a schematic top view showing a pixel electrode having a pixel structure according to the second embodiment of the present invention. FIG. 10 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 11 is a schematic view showing that the pixel electrode of FIG. 9 and the protective layer of FIG. 10 overlap.
As shown in FIG. 9, the pixel electrode 220 includes at least one block electrode (also referred to as a plate electrode) 222, a plurality of first branch electrodes 224, a main electrode 226, and an outer branch electrode 228. ing. Specifically, the block-shaped electrode 222 is an unpatterned electrode region in the pixel electrode 220. That is, the block-shaped electrode 222 does not have any opening, hole, slit, concave groove, or gap. In contrast, the first branch electrode 224, the main electrode 226, and the outer branch electrode 228 are patterned electrode regions in the pixel electrode 220. In this embodiment, the plurality of block electrodes 222 are arranged on both sides of the main electrode 226. The plurality of first branch electrodes 224 are provided so that the block electrodes 222 are arranged on the sides adjacent to each other and close to the edge 222 e of the block electrodes 222. The plurality of first branch electrodes 224 are connected to the main electrode 226, and are slit between the two adjacent first branch electrodes 224 and between the main electrode 226 and the adjacent first branch electrode 224. (Not marked). The plurality of outer branch electrodes 228 are arranged on the side opposite to the edge 222e of the block-shaped electrode 222 and extend radially outward along the other edge 222f of the block-shaped electrode 222. A slit (not labeled) is provided between two adjacent outer branch electrodes 228. As shown in FIG. 9, in the block-shaped electrode 222, the edge 222e is not directly connected to the edge 222f. The orthogonal projection shape (to the substrate) of the block-shaped electrode 222 of the present invention has a polygonal shape, and in the present embodiment, has a hexagonal shape as an example, but is not limited thereto. In this manner, the outer branch electrode 228 and the block-shaped electrode 222 may be formed in a pentagonal shape by the orthogonal projection shape (to the substrate). Various shapes such as a rectangular shape or a zigzag shape can be formed according to the contour shape of the orthogonal projection (to the substrate) of the first branch electrode 224, the outer branch electrode 228, and the block-shaped electrode 222. It is not limited to.

As shown in FIG. 10, the protective layer 240 includes at least one block-like projection pattern (also referred to as a plate-like projection pattern) 242, a plurality of branch projection patterns 244, a main projection pattern 246, and at least one block-like pattern. 248. Specifically, the block-shaped protrusion pattern 242 occupies a considerably large area in the protective layer 240 and is an unpatterned protrusion area. That is, the block-shaped protrusion pattern 242 does not have any opening, hole, slit, concave groove, or gap. The branch projection pattern 244 is a projection in the protective layer 240, and has a concave groove (not denoted by a reference numeral) between the two adjacent branch projection patterns 244, whereby the branch projection pattern 244 and the concave groove are provided. The region where is provided is an uneven region. Since the block pattern (also referred to as a plate pattern) 248 is a recessed region having a considerably large area in the protective layer 240, it is also referred to as a plate-like recess pattern. The thickness of the block-shaped pattern 248 is lower than the thickness of the block-shaped protrusion pattern 242, but may be substantially the same as the thickness of the concave groove.
In the present embodiment, the plurality of branch protrusion patterns 244 are connected to the main protrusion pattern 246. Further, there are concave grooves (not denoted by reference numerals) between two adjacent branching protrusion patterns 244 and between the main protrusion pattern 246 and the adjacent branching protrusion pattern 244. A concave groove (not labeled) between two adjacent branching protrusion patterns 244 is connected to the block-shaped pattern 248. In this embodiment, the block-shaped protrusion pattern 242 is disposed between the branching protrusion patterns 244 in the two separate areas so that the branching protrusion patterns 244 in the two separate areas do not directly contact each other. . In this way, the branching protrusion patterns 244 in the two separate regions are each connected to the main protrusion pattern 246 in that region. Further, the main projection patterns 246 in the two separate areas are not in direct contact with each other and are connected via the block-like projection pattern 242. In the present embodiment, as an example, the four block patterns 248 are provided at the outer corners of the branching protrusion pattern 244, but the present invention is not limited to this.

  FIG. 11 is a schematic view showing that the pixel electrode 220 of FIG. 9 and the protective layer 240 of FIG. 10 overlap. 9 to 11, the pixel electrode 220 is formed above the protective layer 240, and the block-like electrode 222 of the pixel electrode 220 conformally on the plurality of branching protrusion patterns 244 of the protective layer 240. Covering, projecting by the branch projection pattern 244, and recessed by a concave groove (not labeled), a plurality of second branch electrodes 230 are formed. The main electrode 226 and the first branch electrode 224 of the pixel electrode 220 are formed on the block-shaped protrusion pattern 242 of the protective layer 240. The outer branch electrode 228 of the pixel electrode 220 may be formed on the block-shaped pattern 248 of the protective layer 240, and the main electrode 226 of the pixel electrode 220 may be disposed to cross the main protrusion pattern 246 of the protective layer 240. However, it is not limited to this. The main electrode 226 and the main projection pattern 246 are preferably orthogonal to each other as shown in FIG. Incidentally, the main electrode 226 of the pixel electrode 220 includes electrodes arranged in two intersecting directions, for example, the row direction and the column direction. Either one of the two directions is substantially parallel to the main protrusion pattern 246, and the other substantially intersects the main protrusion pattern 246 (eg, substantially perpendicular).

  FIG. 12 is a schematic enlarged view showing the K2 region of FIG. Please refer to FIG. 11 and FIG. The width L1 of the branching protrusion pattern 244 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S1 between the branching protrusion patterns 244 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S1 can be regarded as the width of the concave groove (not labeled). The width L2 of the first branch electrode 224 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S2 between the first branch electrodes 224 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S2 can be regarded as the width of the slit (not labeled). The width L3 of the outer branch electrode 228 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The spacing S3 between the outer branch electrodes 228 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S3 can be regarded as the width of the slit (not labeled). Thus, by adjusting the widths L1, L2, and L3 and the intervals S1, S2, and S3, the tilt direction of the liquid crystal molecules can be finely adjusted so that disclination does not occur.

  Similarly, as shown in FIG. 12, the first branch electrode 224 of the pixel electrode 220 is disposed on the block-shaped protrusion pattern 242 of the protective layer 240. The edge 222e of the block electrode 222 of the pixel electrode 220 further extends to the block protrusion pattern 242 of the protective layer 240. In particular, there is a gap width W1 between the orthogonal projection edge 222e (to the substrate) of the block-like electrode 222 and the orthogonal projection edge 224e (to the substrate) of the first first branch electrode 224a that is closest. . Considering the transmittance, the gap width W1 satisfies the relationship of 0 μm <W1 ≦ 4 μm, preferably satisfies the relationship of 1 μm ≦ W1 ≦ 3 μm, and is most preferably about 2 μm. A distance W2 is provided between the orthogonal projection edge 222e of the block-shaped electrode 222 and the orthogonal projection edge 242e (to the substrate) of the block-shaped protrusion pattern 242. Considering the transmittance, the distance W2 satisfies the relationship of 2 μm ≦ W2 ≦ 5.5 μm, and is most preferably about 3 μm. The sectional view and W1 and W2 are shown in FIG.

  Particularly, the boundary between the block-shaped electrode 222 having the pixel structure and the first first branch electrode 224a is not formed in the concave groove (not denoted by the reference numeral) of the branching protrusion pattern 244 of the protective layer 240, and the protective layer Although provided on 240 block-like projection patterns 242 (see FIG. 7), the present invention is not limited to this. In the present embodiment, the depth d (see FIG. 7) of the concave groove (not labeled) of the branching projection pattern 244 is not limited. As a result, it is possible to prevent the problem of the unstable tilted liquid crystal due to the insufficient depth of the concave groove of the protective layer 240, as well as the W2 junction (that is, the block-shaped electrode 222 and the block-shaped protrusion in plan view). It is possible to improve the efficiency of the liquid crystal corresponding to the portion where the pattern 242 overlaps. Further, in the pixel structure formed by the branch protrusion pattern 244 and the concave groove of the protective layer 240, light leakage in the dark state due to the inclined side wall can be reduced, and a display panel having good transmittance and contrast can be obtained. Can be done.

FIG. 13 is a schematic top view showing a pixel electrode having a pixel structure according to the third embodiment of the present invention. FIG. 14 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 15 is a schematic view showing that the pixel electrode of FIG. 13 and the protective layer of FIG. 14 overlap.
As shown in FIG. 13, the pixel electrode 320 includes at least one block-like electrode (also referred to as a plate-like electrode) 322, a plurality of first branch electrodes 324, a first main electrode 326, a second main electrode 328, have. Specifically, the block electrode 322 is an unpatterned electrode region in the pixel electrode 320. That is, the block-shaped electrode 322 does not have any opening, hole, slit, concave groove, or gap. On the other hand, the first branch electrode 324 is a patterned electrode region in the pixel electrode 320. In particular, as shown in FIG. 13, the plurality of first branch electrodes 324 of the pixel electrode 320 are connected to the plurality of first sub-branch electrodes 3241 connected to the first main electrode 326 and the second main electrode 328. A second sub-branch electrode 3242. Between the two adjacent first sub-branch electrodes 3241 and between the first main electrode 326 and the adjacent first sub-branch electrode 3241, there are slits (not denoted by reference numerals). In addition, there are slits (not labeled) between the two adjacent second sub-branch electrodes 3242 and between the first main electrode 326 and the adjacent second sub-branch electrode 3242. The block electrode 322 is disposed between the first sub-electrode 3241 and the second sub-electrode 3242 so that the first branch electrode 324 and the second branch electrode 328 are not in direct contact with or connected to each other. ing.
The orthogonal projection shape (to the substrate) of the block electrode 322 of the present invention has a polygonal shape. In this embodiment, the zigzag hexagonal shape is used as an example, but the present invention is not limited to this. Thus, the block electrode 222 may be formed in a pentagon shape by the orthogonal projection shape of the second branch electrode 328 and the block electrode 322. Various shapes such as a rectangular shape or a zigzag shape can be formed according to the contour shape of the orthogonal projection (to the substrate) of the first branch electrode 324, the second branch electrode 328, and the block-shaped electrode 322. However, the present invention is not limited to this.

  As shown in FIG. 14, the protective layer 340 includes at least one block-shaped protrusion pattern 342, a plurality of branch protrusion patterns 344, a first main protrusion pattern 346, and a second main protrusion pattern 348. . Specifically, the block-like protrusion pattern (also referred to as a plate-like protrusion pattern) 342 occupies a considerably large area in the protective layer 340 and is an unpatterned protrusion region. That is, the block-shaped protrusion pattern 342 does not have any opening, hole, slit, concave groove, or gap. The branching protrusion pattern 344 is a protrusion in the protective layer 340, and has a concave groove (not denoted by a reference numeral) between two adjacent branching protrusion patterns 344, whereby the branching protrusion pattern 344 and the concave groove are provided. The region where is provided is an uneven region. In particular, as shown in FIG. 14, the plurality of branch protrusion patterns 344 of the protective layer 340 are connected to the plurality of first branch protrusion patterns 3441 connected to the first main protrusion pattern 346 and the second main protrusion pattern 348. And a plurality of second branching protrusion patterns 3442. In the present embodiment, as an example, three block-shaped protrusion patterns 342 are provided. The first branch protrusion pattern 3441 is provided between two adjacent block-like protrusion patterns 342, and the second branch protrusion pattern 3442 is provided between two adjacent block-like protrusion patterns 342, each having two regions. The first branch protrusion pattern 3441 and the second branch protrusion pattern 3442 are not in direct contact with or connected to each other. The first main protrusion pattern 346 and the second main protrusion pattern 348 connected to the first branch protrusion pattern 3441 and the second branch protrusion pattern 3442, respectively, in two separate regions are not in direct contact with or connected to each other, and are in a block shape therebetween Although connected via the protrusion pattern 342, the present invention is not limited to this.

  FIG. 15 is a schematic diagram showing that the pixel electrode 320 of FIG. 13 and the protective layer 340 of FIG. 14 overlap. 13 to 15 together, the pixel electrode 320 is formed above the protective layer 340, and the block-like electrode 322 of the pixel electrode 320 conformally on the plurality of branching protrusion patterns 344 of the protective layer 340. Covering, projecting with the branching projection pattern 344, recessed downward with a concave groove (not labeled), and arranged to form a plurality of second branch electrodes 330. In particular, the block-shaped protrusion pattern 342 of the protective layer 340 includes the first sub-branch electrode 3241 and the second sub-branch electrode 3242 such that the block-shaped protrusion pattern 342 overlaps the first sub-branch electrode 3241 and the second sub-branch electrode 3242. Is provided below. The edge 322e of the block electrode 322 of the pixel electrode 320 is not formed in the concave groove (refer to FIG. 7, which is not labeled) in the branching protrusion pattern 344 of the protective layer 340, and is not formed in the protective layer 340. It extends to the block-shaped protrusion pattern 342. In the present embodiment, the depth of the concave groove (not labeled) of the branching projection pattern 344 is not limited. The first main electrode 326 of the pixel electrode 320 may be disposed to intersect the first main protrusion pattern 346 and the second main protrusion pattern 348 of the protective layer 340, but is not limited thereto. As shown in FIG. 15, the first main electrode 326 and the first main protrusion pattern 346 are preferably orthogonal to each other. Incidentally, the first main electrode 326 of the pixel electrode 320 includes electrodes arranged in two intersecting directions, for example, the row direction and the column direction. One of the two directions is substantially parallel to the first main protrusion pattern 346 and the second main protrusion pattern 348, and the other is substantially equal to the first main protrusion pattern 346 and the second main protrusion pattern 348. (E.g., substantially vertical).

  FIG. 16 is a schematic enlarged view showing a region K3 in FIG. Please refer to FIG. 15 and FIG. The width L1 of the first branch protrusion pattern 3441 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S1 between the first branch protrusion patterns 3441 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S1 can be regarded as the width of the concave groove (not labeled). The width L2 of the first sub-branch electrode 3241 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S2 between the first sub-branch electrodes 3241 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S2 can be regarded as the width of the slit (not labeled). Thus, by adjusting the widths L1 and L2 and the intervals S1 and S2, the tilt direction of the liquid crystal molecules can be finely adjusted so that disclination does not occur. In particular, referring to FIGS. 15 and 16 together, the width and interval of the second branch protrusion pattern 3442 are substantially the same as the width L1 and interval S1 of the first branch protrusion pattern 3441. The first branch protrusion pattern 3441 may be substantially the same as or different from the width and interval of the second branch protrusion pattern 3442, but is not limited thereto. Similarly, the width and interval of the second sub-branch electrode 3242 are substantially the same as the width L2 and interval S2 of the first sub-branch electrode 3241. Further, the first sub-branch electrode 3241 may be substantially the same as or different from the width and interval of the second sub-branch electrode 3242, but is not limited thereto.

  As shown in FIG. 16, similarly, the first branch electrode 324 of the pixel electrode 320 is disposed on the block-shaped protrusion pattern 342 of the protective layer 340. A gap width W1 is provided between the orthogonal projection edge 322e (to the substrate) of the block-shaped electrode 322 and the orthogonal projection edge 324e (to the substrate) of the first first branch electrode 324a which is the closest. Considering the transmittance, the gap width W1 satisfies the relationship of 0 μm <W1 ≦ 4 μm, preferably satisfies the relationship of 1 μm ≦ W1 ≦ 3 μm, and is most preferably about 2 μm. A distance W2 is provided between the orthogonal projection edge 322e of the block-shaped electrode 322 and the orthogonal projection edge 342e (to the substrate) of the block-shaped protrusion pattern 342. Considering the transmittance, the distance W2 satisfies the relationship of 2 μm ≦ W2 ≦ 5.5 μm, and is most preferably about 3 μm. The sectional view and W1 and W2 are shown in FIG.

  In particular, the boundary between the block-shaped electrode 322 having the pixel structure and the first first branch electrode 324a includes the branch protrusion pattern 344 (the first branch protrusion pattern 3441 and the second branch protrusion pattern 3442) of the protective layer 340. ) (Not shown) and provided on the protruding block-like projection pattern 342 of the protective layer 340 (see FIG. 7). In the present embodiment, the depth d (see FIG. 7) of the concave grooves (not denoted by reference numerals) of the first branch protrusion pattern 3441 and the second branch protrusion pattern 3442 is not limited. As a result, the pixel structure of the present embodiment can prevent the problem of the unstable tilted liquid crystal due to insufficient depth of the concave groove of the protective layer 340, and also has a W2 junction (that is, in plan view). It is possible to improve the efficiency of the liquid crystal corresponding to the portion where the block-shaped electrode 322 and the block-shaped protrusion pattern 342 overlap. In addition, in the pixel structure formed by the branch protrusion pattern 344 and the concave groove of the protective layer 340, light leakage in the dark state due to the inclined side wall can be reduced, and a display panel having good transmittance and contrast can be obtained. Can be done.

FIG. 17 is a schematic top view showing a pixel electrode having a pixel structure according to the fourth embodiment of the present invention. FIG. 18 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 19 is a schematic view showing that the pixel electrode of FIG. 17 and the protective layer of FIG. 18 overlap.
As shown in FIG. 17, the pixel electrode 420 has at least one block-like electrode 422 and a plurality of first branch electrodes 424. The block electrode 422 includes a plurality of sub-block electrodes 4221. Specifically, in particular, the sub-block electrode 4221 of the block electrode (also referred to as a plate electrode) 422 is an unpatterned electrode region in the pixel electrode 420. That is, the sub-block electrode 4221 does not have any opening, hole, slit, concave groove, or gap. On the other hand, the first branch electrode 424 is a patterned electrode region in the pixel electrode 420. In particular, in the present embodiment, only one first branch electrode 424 is disposed between two adjacent sub-block electrodes 4221, but the present invention is not limited to this. The first branch electrode 424 is connected to a main electrode (not labeled), and between the first branch electrode 424 and an adjacent electrode (for example, the sub-block electrode 4221 or another first branch electrode 424). May have a slit (not labeled). Further, two adjacent block electrodes 422 are not in direct contact with or connected to each other. The orthogonal projection shape (to the substrate) of the sub-block electrode 4221 of the present invention may have a polygonal shape, for example, a zigzag shape, but is not limited thereto. As described above, a rectangular shape or a zigzag shape can be formed by the contour shape of the orthogonal projection (to the substrate) of the first branch electrode 424 and the block-like electrode 422, but the present invention is not limited thereto.

  Referring to FIG. 18, the protective layer 440 includes at least one block-shaped protrusion pattern (also referred to as a plate-shaped protrusion pattern) 442 and a plurality of branch protrusion patterns 444. In particular, as shown in FIG. 18, each block-shaped protrusion pattern 442 of the protective layer 440 further includes a plurality of sub-block-shaped protrusion patterns 4421. In particular, in this embodiment, as an example, only one branching projection pattern 444 is disposed between two adjacent sub-block-like projection patterns 4421. You may further have a ditch | groove (a code | symbol is not attached | subjected) between the branching protrusion pattern 444 and the adjacent pattern (for example, subblock-like protrusion pattern 4421 or another branching protrusion pattern 444). Further, the two adjacent sub-block-shaped protrusion patterns 4421 are not in direct contact with or connected to each other. Specifically, the block-shaped protrusion pattern 442 and the sub-block-shaped protrusion pattern 4421 occupy a considerably large area in the protective layer 440 and are unpatterned regions. That is, the block-shaped protrusion pattern 442 and the sub-block-shaped protrusion pattern 4421 do not have any opening, hole, slit, concave groove, or gap. A region where the branching protrusion pattern 444 and the concave groove (not denoted by reference numerals) are provided is an uneven region in the protective layer 440. In this embodiment, the branch protrusion pattern 444 is connected to the main protrusion pattern (not labeled). In particular, the orthogonal projection shape (to the substrate) of the block-like protrusion pattern 442 may be an X-shape which is a zigzag shape and distinguishes the main protrusion patterns in two different directions from each other and is an intersection of the two directions.

  FIG. 19 is a schematic diagram showing that the pixel electrode 420 of FIG. 17 and the protective layer 440 of FIG. 18 overlap. Referring to FIGS. 17 to 19 together, the pixel electrode 420 is formed above the protective layer 440. The block electrode 422 of the pixel electrode 420 conformally covers the plurality of branching protrusion patterns 444 of the protective layer 440, protrudes by the plurality of branching protrusion patterns 444, and is recessed by a plurality of concave grooves (not denoted by reference numerals). A plurality of second branch electrodes 426 are formed. The first branch electrode 424 of the pixel electrode 420 is disposed on the block-shaped protrusion pattern 442 of the protective layer 440. The edge 422e of the block electrode 422 of the pixel electrode 420 further extends to the block protrusion pattern 442 of the protective layer 440.

  FIG. 20 is a schematic enlarged view showing the K4 region of FIG. Please refer to FIG. 19 and FIG. 20 together. The width L1 of the branching protrusion pattern 444 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S1 between the branching protrusion pattern 444 and the block-like protrusion pattern 442 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S1 can be regarded as the width of the concave groove (not labeled). Each width L2 of the first branch electrode 424 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Thus, by adjusting the widths L1 and L2 and the interval S1, the tilt direction of the liquid crystal molecules can be finely adjusted so that no disclination occurs.

  Similarly, as shown in FIG. 20, the first branch electrode 424 of the pixel electrode 420 is disposed on the block-shaped protrusion pattern 442 of the protective layer 440. In particular, there is a gap width W1 between the orthogonal projection edge 422e (to the substrate) of the block-like electrode 422 and the orthogonal projection edge 424e (to the substrate) of the first first branch electrode 424a that is closest. . Considering the transmittance, the gap width W1 satisfies the relationship of 0 μm <W1 ≦ 4 μm, preferably satisfies the relationship of 1 μm ≦ W1 ≦ 3 μm, and is most preferably about 2 μm. In this embodiment, since only one first branch electrode 424 is arranged between two adjacent sub-block electrodes 4221, the gap width W1 can be regarded as the width of the slit between the electrodes. Further, there is a distance W2 between the orthogonal projection edge 422e of the block-shaped electrode 422 and the orthogonal projection edge 442e (to the substrate) of the block-shaped projection pattern 442. Considering the transmittance, the distance W2 satisfies the relationship of 2 μm ≦ W2 ≦ 5.5 μm, and is most preferably about 3 μm. The sectional view and W1, W2 are shown in FIG.

  In particular, the boundary between the block-shaped electrode 422 having the pixel structure and the first first branch electrode 424a is not formed in the concave groove (not denoted by reference numeral) of the projecting branch projection pattern 444 of the protective layer 440. It is provided on the protruding block-like pattern 442 of the protective layer 440 (see FIG. 7). In the present embodiment, the depth d (see FIG. 7) of the concave groove (not labeled) of the branching projection pattern 444 is not limited. Accordingly, it is possible to prevent the problem of the unstable tilted liquid crystal due to the insufficient depth of the concave groove of the protective layer 440, and it is possible to improve the efficiency of the liquid crystal corresponding to the W2 region. . Further, in the pixel structure formed by the branch protrusion pattern 444 and the concave groove of the protective layer 440, light leakage in the dark state due to the inclined side wall can be reduced, and a display panel having good transmittance and contrast can be obtained. Can be done.

FIG. 21 is a schematic top view showing a pixel electrode having a pixel structure according to the fifth embodiment of the present invention. FIG. 22 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 23 is a schematic diagram showing that the pixel electrode of FIG. 21 and the protective layer of FIG. 22 overlap.
As shown in FIG. 21, the pixel electrode 520 has at least one block-like electrode 522 and a plurality of first branch electrodes 524. The block electrode 522 includes a plurality of sub-block electrodes 5221. The sub-block electrode 5221 is an unpatterned electrode region in the pixel electrode 520. That is, the block-shaped electrode 522 and the sub-block-shaped electrode 5221 do not have any opening, hole, slit, concave groove, or gap. On the other hand, the first branch electrode 524 is a patterned electrode region in the pixel electrode 520. Incidentally, the pixel electrode 520 shown in FIG. 21 is similar to the pixel electrode 420 shown in FIG. 17, and the similar components are shown in the fourth embodiment, so the description thereof is omitted here. . The difference between the two embodiments is that, in this embodiment, only two first branch electrodes 524 are arranged between two adjacent sub-block electrodes 5221, but the present invention is not limited to this.

  Referring to FIG. 22, the protective layer 540 includes at least one block-shaped protrusion pattern 542 and a plurality of branch protrusion patterns 544. In particular, as shown in FIG. 22, the block-shaped protrusion pattern 542 of the protective layer 540 further includes a plurality of sub-block-shaped protrusion patterns 5421. Incidentally, the protective layer 540 shown in FIG. 22 is similar to the protective layer 440 shown in FIG. 18, and the similar components have been described in the fourth embodiment, so the description thereof is omitted here. To do. As shown in FIG. 22, the difference between the two embodiments is that at least one branching protrusion pattern 544 is arranged between two adjacent sub-block-like protrusion patterns 5421. In this embodiment, as an example, three branching protrusion patterns 544 are arranged between two adjacent sub-block-like protrusion patterns 5421.

  FIG. 23 is a schematic diagram showing that the pixel electrode 520 of FIG. 21 and the protective layer 540 of FIG. 22 overlap. Referring to FIGS. 21 to 23 together, the pixel electrode 520 is formed above the protective layer 540, and the block-like electrode 522 of the pixel electrode 520 conformally on the plurality of branching protrusion patterns 544 of the protective layer 540. Covering, projecting by a plurality of branch projection patterns 544, and recessed by a plurality of concave grooves (not denoted by reference numerals), a plurality of second branch electrodes 526 are formed. The first branch electrode 524 of the pixel electrode 520 is disposed on the block-shaped protrusion pattern 542 of the protective layer 540. The edge 522e of the block electrode 522 of the pixel electrode 520 further extends to the block protrusion pattern 542 of the protective layer 540.

  FIG. 24 is a schematic enlarged view showing a region K5 in FIG. Please refer to FIG. 23 and FIG. 24 together. The width L1 of the branching protrusion pattern 544 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S1 between the branching protrusion patterns 544 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S1 can be regarded as the width of the concave groove (not labeled). The width L2 of the first branch electrode 524 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. The interval S2 between the first branch electrodes 524 is in the range of about 1 μm to about 10 μm, and preferably in the range of about 2 μm to about 6 μm. Here, the interval S2 can be regarded as the width of the slit (not labeled). Thus, by adjusting the widths L1 and L2 and the intervals S1 and S2, the tilt direction of the liquid crystal molecules can be finely adjusted so that disclination does not occur.

  Similarly, as shown in FIG. 24, the first branch electrode 524 of the pixel electrode 520 is disposed on the block-shaped protrusion pattern 542 of the protective layer 540. In particular, there is a gap width W1 between the orthogonal projection edge 522e (to the substrate) of the block-like electrode 522 and the orthogonal projection edge 524e (to the substrate) of the first first branch electrode 524a that is closest. . Considering the transmittance, the gap width W1 satisfies the relationship of 0 μm <W1 ≦ 4 μm, preferably satisfies the relationship of 1 μm ≦ W1 ≦ 3 μm, and is most preferably about 2 μm. Further, there is a distance W2 between the orthogonal projection edge 522e of the block-like electrode 522 and the orthogonal projection edge 542e (to the substrate) of the block-like projection pattern 542. Considering the transmittance, the distance W2 satisfies the relationship of 2 μm ≦ W2 ≦ 5.5 μm, and is more preferably about 3 μm. The sectional view and W1 and W2 are shown in FIG.

  In particular, the boundary between the block-shaped electrode 522 having the pixel structure and the first first branch electrode 524a is not formed in the concave groove (not denoted by reference numeral) of the protruding branching protrusion pattern 544 of the protective layer 540, It is provided on the protruding block-like projection pattern 542 of the protective layer 540 (see FIG. 7). In the present embodiment, the depth d (see FIG. 7) of the concave groove (not labeled) of the branching projection pattern 544 is not limited. This can prevent the problem of unstable tilted liquid crystal due to insufficient depth of the concave groove of the protective layer 540, and also the W2 junction (that is, the block-like electrode 522 and the block-like protrusion in plan view). It is possible to improve the efficiency of the liquid crystal corresponding to the portion where the pattern 542 overlaps. In addition, in the pixel structure formed by the branch protrusion pattern 544 and the concave groove of the protective layer 540, light leakage in the dark state due to the inclined side wall can be reduced, and a display panel having good transmittance and contrast can be obtained. Can be done.

FIG. 25 is a schematic top view showing a pixel electrode having a pixel structure according to the sixth embodiment of the present invention. FIG. 26 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 27 is a schematic view showing that the pixel electrode of FIG. 25 and the protective layer of FIG. 26 overlap.
As shown in FIG. 25, the pixel electrode 620 includes a plurality of branch electrodes 622 and a main electrode 624. A gap (also referred to as a slit) 626 is provided between two adjacent branch electrodes 622. The branch electrode 622 is connected to the main electrode 624 and extends from the main electrode 624 along a plurality of directions. In this embodiment, the main electrode 624 is formed in a cross shape, but is not limited thereto.

  As shown in FIG. 26, the protective layer 640 has a plurality of branch protrusion patterns 642 and a main protrusion pattern 644. At least one groove (also referred to as a concave groove) 646 is provided between two adjacent branching protrusion patterns 642. The plurality of branch protrusion patterns 642 are connected to the main protrusion pattern 644 and extend from the main protrusion pattern 644 along a plurality of directions. In the present embodiment, the main protrusion pattern 644 is formed in a cross shape, but is not limited thereto.

  FIG. 27 is a schematic diagram showing that the pixel electrode 620 of FIG. 25 and the protective layer 640 of FIG. 26 overlap. Referring to FIGS. 25 to 27 together, the pixel electrode 620 is formed above the protective layer 640, and each branch electrode 622 of the pixel electrode 620 is disposed corresponding to one groove 646 of the protective layer 640. Each of the gaps 626 of the pixel electrode 620 is disposed corresponding to one branching protrusion pattern 642 of the protective layer 640. The branch electrode 622 extends from the groove 646 to the adjacent branching protrusion patterns 642 on both sides, and is arranged so that the gap 626 overlaps the branching protrusion pattern 642, but is not limited thereto. As shown in FIG. 27, the main electrode 624 and the main projection pattern 644 are arranged so as to overlap each other. Incidentally, since the gap 626 of the branch electrode 622 is provided on the branch protrusion pattern 642, the dark line of the pixel electrode 620 can be thinned. In the present embodiment, as an example, the width of the main electrode 624 is formed to be substantially larger than the width of the main protrusion pattern 644, but is not limited thereto.

  FIG. 28 is a schematic enlarged view showing the K6 region of FIG. FIG. 29 is a schematic sectional view taken along line J-J ′ in FIG. 27. Referring to FIG. 27, FIG. 28 and FIG. 29 together, the gap 626 of two adjacent branch electrodes 622 of the pixel electrode 620 has a distance a and satisfies the relationship of a ≠ 0. The distance a is preferably 0 μm <a ≦ 3 μm, and most preferably 2 μm in consideration of transmittance, but is not limited thereto. There is a distance b between the orthogonal projection edge 622e (to the substrate) of the branch electrode 622 of the pixel electrode 620 and the orthogonal projection edge 646e (to the substrate) of the groove 646 of the protective layer 640, and b ≠ 0. Satisfy the relationship. The distance b is preferably 1.5 μm ≦ b ≦ 10 μm, and most preferably 1.5 μm, but is not limited thereto. In this embodiment, the width c of the groove 646 of the protective layer 640 satisfies the relationship of 3 μm <c ≦ (a + 2b) μm.

  The width L4 of the branch electrode 622 of the pixel electrode 620 is in the range of about 1 μm to about 10 μm. The width L5 of the branching protrusion pattern 642 of the protective layer 640 is in the range of about 1 μm to about 10 μm. Incidentally, the width c of the groove 646 is the same as the width L5 of the branching protrusion pattern 642, but is not limited thereto. In this embodiment, by adjusting the widths L4, L5, c and the distances a, b, the tilt direction of the liquid crystal molecules can be finely adjusted so that disclination does not occur.

  In particular, even when the width of the branch electrode is not small, the alignment stability of the liquid crystal molecules can be improved. In addition, the pixel structure of this embodiment can prevent the problem that the tilt of the liquid crystal becomes unstable due to the insufficient depth of the concave groove of the protective layer 640, and the junction b (that is, in plan view). It is possible to improve the efficiency of the liquid crystal corresponding to the portion where the branch electrode 622 and the branch protrusion pattern 642 overlap. In addition, in the pixel structure formed by the branch protrusion pattern 642 of the protective layer 640, light leakage in a dark state due to the inclined sidewall can be reduced, and a display panel having favorable transmittance and contrast can be obtained. it can.

FIG. 30 is a schematic top view showing a pixel electrode having a pixel structure according to the seventh embodiment of the present invention. 31 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 32 is a schematic view showing that the pixel electrode of FIG. 30 and the protective layer of FIG. 31 overlap.
Since the present embodiment is similar to the embodiment shown in FIG. 27, the same or similar elements are denoted by the same or similar reference numerals, and redundant description is omitted. Similarly, as illustrated in FIG. 30, the pixel electrode 720 includes a plurality of branch electrodes 722 and a main electrode 724. A gap (also referred to as a slit) 726 is provided between two adjacent branch electrodes 722. The branch electrode 722 is connected to the main electrode 724 and extends from the main electrode 724 along a plurality of directions.

  Similarly, as shown in FIG. 31, the protective layer 740 includes a plurality of branch protrusion patterns 742 and a main protrusion pattern 744. At least one groove (also referred to as a concave groove) 746 is provided between two adjacent branching protrusion patterns 742. The plurality of branch protrusion patterns 742 are connected to the main protrusion pattern 744 and extend from the main protrusion pattern 744 along a plurality of directions.

  The difference between the embodiment shown in FIG. 32 and the embodiment shown in FIG. 27 is that each of the branch electrodes 722 of the pixel electrode 720 is arranged corresponding to one of the branching protrusion patterns 742 of the protective layer 740, Each of the gaps 726 of the electrode 720 is disposed corresponding to one of the grooves 746 of the protective layer 740. The branch electrode 722 extends from the branch protrusion pattern 742 to the adjacent grooves 746, and the gap 726 is disposed so as to overlap the adjacent grooves 746. Similarly, the main electrode 724 is disposed so as to overlap the main projection pattern 744. Incidentally, in the present embodiment, the width of the main electrode 724 is formed larger than the width of the main projection pattern 744, but is not limited thereto.

  FIG. 33 is a schematic enlarged view showing a region K7 in FIG. Referring to FIGS. 32 and 33 together, a gap 726 between two branch electrodes 722 adjacent to the pixel electrode 720 has a distance a and satisfies a relationship of a ≠ 0. The distance a is preferably 0 μm <a ≦ 3 μm, and most preferably 2 μm in consideration of transmittance, but is not limited thereto. There is a distance b between the orthogonal projection edge 722e (to the substrate) of the branch electrode 722 of the pixel electrode 720 and the orthogonal projection edge 746e (to the substrate) of the groove 746 of the protective layer 740, and b ≠ 0. Satisfy the relationship. The distance a is preferably 1.5 μm ≦ b ≦ 10 μm, and most preferably 1.5 μm, but is not limited thereto. In the present embodiment, the width L3 of the groove 746 of the protective layer 740 satisfies the relationship of 3 μm <L3 ≦ (a + 2b) μm.

The width L4 of the branch electrode 722 of the pixel electrode 720 is in the range of about 1 μm to about 10 μm.
The width c of the branching protrusion pattern 742 of the protective layer 740 is in the range of about 1 μm to about 10 μm. In this embodiment, by adjusting the widths L4, L3, c and the distances a, b, the tilt direction of the liquid crystal molecules can be finely adjusted so that disclination does not occur.

  In particular, even when the width of the branch electrode is not small, the alignment stability of the liquid crystal molecules can be improved. In addition, the pixel structure of this embodiment can prevent the problem of the unstable tilted liquid crystal due to insufficient depth of the concave groove of the protective layer 740, as well as the junction b (ie, branch in plan view). It is possible to improve the efficiency of the liquid crystal corresponding to the portion where the electrode 722 and the branching protrusion pattern 742 overlap. In addition, in the pixel structure formed by the branching protrusion pattern 742 of the protective layer 740, light leakage in the dark state due to the inclined sidewall can be reduced, and a display panel having favorable transmittance and contrast can be obtained. it can.

FIG. 34 is a schematic top view showing a pixel electrode 820 having a pixel structure according to the eighth embodiment of the present invention. FIG. 35 is a schematic top view showing a protective layer provided below the pixel electrode of FIG. FIG. 36 is a schematic diagram showing that the pixel electrode of FIG. 34 and the protective layer of FIG. 35 overlap.
As shown in FIG. 34, the pixel electrode 820 includes a plurality of branch electrodes 822, at least one block-shaped electrode 830, a main electrode 824, and a plurality of outer branch electrodes 826. A gap (also referred to as a slit) 828 is provided between two adjacent branch electrodes 822. The branch electrode 822 is connected to the main electrode 824 and extends from the main electrode 824 along a plurality of directions. The block electrode (also referred to as a plate electrode) 830 is an unpatterned electrode region in the pixel electrode 820. That is, the block-shaped electrode 830 does not have any opening, hole, slit, concave groove, or gap. Here, the plurality of block electrodes 830 are provided on both sides of the main electrode 824. The plurality of branch electrodes 822 are provided on the side where the block electrodes 830 are adjacent to each other so as to be close to the edges of the block electrodes 830. The plurality of branch electrodes 822 are connected to the main electrode 824. The plurality of outer branch electrodes 826 are disposed on the other side of the block-shaped electrode 830 (opposite side of the edge of the block-shaped electrode 830) and extend radially outward along the other edge of the block-shaped electrode 830. ing. A slit (not labeled) is provided between two adjacent outer branch electrodes 826. As shown in FIG. 34, the two edges of the block electrode 830 are not directly connected to each other. The orthogonal projection shape (to the substrate) of the block-shaped electrode 830 of this embodiment has a polygonal shape, for example, a hexagonal shape, but is not limited thereto. In this way, the outer branch electrode 826 and the block-shaped electrode 830 may be formed in a pentagonal shape by the contour shape of the orthogonal projection (to the substrate). A rectangular shape or a zigzag shape can be formed according to the contour shape of the orthogonal projection (to the substrate) of the branch electrode 822, the outer branch electrode 826, and the block-shaped electrode 830, but is not limited thereto. The outer branch electrode 826 is connected to the block electrode 830. In this embodiment, the main electrode 824 is formed in a cross shape, but is not limited thereto.

  As shown in FIG. 35, the protective layer 840 has a plurality of branch protrusion patterns 842, a main protrusion pattern 844, and at least one block-shaped pattern 846. There is at least one groove (also referred to as a concave groove) 848 between two adjacent branching protrusion patterns 842. Since the block-shaped pattern (also referred to as a plate-shaped pattern) 846 is a recessed region having a considerably large area in the protective layer 840, it is also referred to as a plate-shaped recessed pattern. The thickness of the block pattern 846 is lower than the thickness of the branch protrusion pattern 842 and the main protrusion pattern 844, but may be substantially the same as the thickness of the concave groove. The plurality of branch protrusion patterns 842 are connected to the main protrusion pattern 844 and extend from the main protrusion pattern 844 along a plurality of directions. A concave groove 848 between two adjacent branching protrusion patterns 842 is connected to the block-shaped pattern 846. Further, in the present embodiment, as an example, the four block patterns 846 are provided at the corners on the outer side of the branching protrusion pattern 842, but the present invention is not limited to this. In this embodiment, the main projection pattern 844 is formed in a cross shape, but is not limited thereto.

FIG. 36 is a schematic view showing that the pixel electrode 820 of FIG. 34 and the protective layer 840 of FIG. 35 overlap. 34 to 36, the pixel electrode 820 is formed above the protective layer 840, and each branch electrode 822 of the pixel electrode 820 is disposed corresponding to one groove 848 of the protective layer 840. ing. Each of the branch electrodes 822 extends from the inside of the groove 848 to the adjacent branching protrusion patterns 842 on both sides, and is arranged so that the gap 828 overlaps the branching protrusion pattern 842, but is not limited thereto. The outer branch electrode 826 is disposed on the block pattern 846 of the protective layer 840.
The block electrode 830 of the pixel electrode 820 conformally covers the plurality of branching protrusion patterns 842 in other regions of the protective layer 840, protrudes by the branching protrusion pattern 842, is recessed by the recessed groove 848, and has a plurality of second branches. Electrodes (not labeled) are provided so as to be formed. As shown in FIG. 36, the main electrode 824 and the main projection pattern 844 overlap each other. In the present embodiment, as an example, the width of the main electrode 824 is formed to be substantially larger than the width of the main protrusion pattern 844, but is not limited thereto.

  FIG. 37 is a schematic enlarged view showing a region K8 in FIG. 36 and 37 together, a gap 828 between two adjacent branch electrodes 822 of the pixel electrode 820 has a distance a and satisfies a relationship of a ≠ 0. The distance a is preferably 0 μm <a <3 μm, and most preferably 2 μm in consideration of transmittance, but is not limited thereto. There is a distance b between the orthogonal projection edge 822e (to the substrate) of the branch electrode 822 of the pixel electrode 820 and the orthogonal projection edge 848e (to the substrate) of the groove 848 of the protective layer 840, and b ≠ 0. Satisfy the relationship. The distance b is preferably 1.5 μm ≦ b ≦ 10 μm, and most preferably 1.5 μm in consideration of transmittance, but is not limited thereto. In this embodiment, the width c of the groove 848 of the protective layer 840 satisfies the relationship of 3 μm <c ≦ (a + 2b) μm.

  Further, the width L3 of the outer branch electrode 826 of the pixel electrode 820 is in the range of about 1 μm to about 10 μm, and the interval S3 of the outer branch electrode 826 is in the range of about 1 μm to about 10 μm. The width L4 of the branch electrode 822 is in the range of about 1 μm to about 10 μm, and the interval S4 of the branch electrode 822 is in the range of about 1 μm to about 10 μm. The width L5 of the branch protrusion pattern 842 disposed below the branch electrode 822 is in the range of about 1 μm to about 10 μm, and the interval S5 between the branch protrusion patterns 842 disposed below the branch electrode 822 is about 1 μm to about 10 μm. It is in the range of 10 μm. In other words, the interval S5 is regarded as the width c of the concave groove 848. A width L6 of the branching protrusion pattern 842 disposed below the block-like electrode 830 is in the range of about 1 μm to about 10 μm, and an interval S6 between the branching protrusion patterns 842 disposed below the block-like electrode 830 is about 1 μm. To about 10 μm. Incidentally, in this embodiment, the widths L5 and L6 of the branching protrusion pattern 842 may be the same or different from each other. Further, the intervals S5 and S6 of the branching protrusion patterns 842 may be the same or different. In this way, by adjusting the widths L3, L4, L5, L6, c and the distances a and b, the tilt direction of the liquid crystal molecules can be finely adjusted so that disclination does not occur.

  In particular, even when the width of the branch electrode is not small, the alignment stability of the liquid crystal molecules can be improved. In addition, the pixel structure of this embodiment can prevent the problem of unstable liquid crystal due to insufficient depth of the concave groove of the protective layer 840, and also has a junction b (that is, a branch in plan view). It is possible to improve the efficiency of the liquid crystal corresponding to the portion where the electrode 822 and the branching protrusion pattern 842 overlap. In addition, in the pixel structure formed by the branching protrusion pattern 842 of the protective layer 840, light leakage in the dark state due to the inclined sidewall can be reduced, and a display panel having favorable transmittance and contrast can be obtained. it can.

According to one embodiment of the present invention, the display panel 1000 includes a plurality of pixel structures described in any of the above embodiments, and pixel cells are configured by at least three pixel structures.
In particular, the width or interval of the first branch electrode or branch electrode of at least one pixel structure in each of the pixel cells is the width or interval (slit) of the first branch electrode or branch electrode of another pixel structure in the pixel cell. Is different. For example, one pixel cell of the display panel 1000 may be formed by the pixel structure described in the first, second, and third embodiments. In this pixel cell, the width L2 of the first branch electrode 124 in the pixel structure of the first embodiment is equal to the width L2 of the first branch electrodes 224 and 324 in the pixel structure of the second embodiment or the third embodiment. And may be different. Alternatively, two of the three pixel structures may use the pixel structure shown in the first embodiment, and other pixel structures may use the pixel structure shown in the first embodiment or the second embodiment. Good. The above description is illustrative only and should not be construed as limiting the invention. As described above, by adjusting the width or interval of the first branch electrode or the branch electrode, the alignment direction of the liquid crystal molecules is finely adjusted so that the color shift does not occur in the display panel 1000 according to an embodiment of the present invention. can do.

  Hereinafter, the relationship between the transmittance of the display panel and the pixel structure according to some embodiments of the present invention will be described with reference to the drawings.

  FIG. 38 is a schematic view showing the relationship between the transmittance of the display panel and the pixel structure according to the first embodiment of the present invention. FIG. 39 is a schematic diagram showing the relationship between the transmittance and the pixel structure of the display panel according to the comparative example. Here, the horizontal axis represents distance (μm), and the vertical axis represents normalized transmittance (%) (no unit). As shown in FIG. 38, the boundary between the block-shaped electrode 122 having the pixel structure according to the first embodiment of the present invention and the first first branch electrode 124a is formed in the protruding region of the block-shaped protrusion pattern 142. Is provided. That is, in FIG. 38, as an example, the block-shaped electrode 122 extends over the block-shaped protrusion pattern 142. On the other hand, in the comparative example shown in FIG. 39, the boundary between the block electrode 122 ′ and the first first branch electrode 124 a ′ is provided in the concave groove 145 of the branching projection pattern 144. Specifically, the boundary between the block-shaped electrode 122 ′ shown in FIG. 39 and the first first branch electrode 124a ′ is provided in the concave groove 145 of the branch projection pattern 144, that is, the block-shaped electrode 122. The edge of 'does not extend to the block-like projection pattern 142 but is provided in the concave groove 145. The other side of the boundary between the block electrode 122 ′ and the first first branch electrode 124 a ′ is provided on the block protrusion pattern 142. That is, the first first branch electrode 124 a ′ is provided only on the block-shaped protrusion pattern 142. In addition to the above case, one side of the boundary between the block-shaped electrode 122 ′ of the comparative example and the first first branch electrode 124 a ′ may overlap the edge of the branching protrusion pattern 144. That is, that is, the block-shaped electrode 122 ′ is in the concave groove 145, and the edge of the block-shaped electrode 122 ′ does not extend to the block-shaped protrusion pattern 142, and is near one side of the block-shaped protrusion pattern 142. And the first first branch electrode 124 a ′ is provided only on the block-shaped protrusion pattern 142.

  As shown in FIG. 38, the display panel according to the first embodiment can always have good transmittance. In other words, the design of the distance W2 can prevent the problem of dark lines due to the occurrence of liquid crystal disclination at the boundary, and a display panel having good transmittance and contrast can be obtained. be able to. On the other hand, as can be seen in FIG. 39, the transmittance is significantly reduced at the boundary between the block-shaped electrode 122 'and the first first branch electrode 124a'. This is because the twist angle of the liquid crystal molecules here deviates from a predetermined 45 degrees with respect to the polarizing plate, and the transmittance is greatly reduced. In the comparative example, even when the edge of the block-shaped electrode 122 ′ is provided near one side of the block-shaped protrusion pattern 142, the transmittance is still significantly reduced. That is, when the distance W2 is not provided (for example, W2 is 0 or less), a dark line due to the occurrence of liquid crystal disclination at the boundary is generated. When W2 is 0, it indicates that the edge of the block-shaped electrode 122 ′ is in contact with the side of the block-shaped protrusion pattern 142 but is provided in the concave groove 145. When W2 is less than 0, the edge of the block electrode 122 ′ is separated from the side of the block protrusion pattern 142, and the orthogonal projection (to the substrate) of the block electrode 122 ′ is on the block protrusion pattern 142. It is shown that it is not provided but is provided in the groove 145 or on the branching protrusion pattern 144. The effects and explanations related to W2 and the boundary shown in FIG. 38 are also applicable to the above-described embodiments shown in FIGS. 12, 16, 20, and 24, for example. In addition, this example has the effect of the above-described example as compared with the comparative example shown in FIG.

  FIG. 40 is a schematic diagram showing the relationship between the transmittance of the display panel according to the first embodiment of the invention and W1. As shown in FIG. 40, the horizontal axis indicates the distance (μm) of the gap width W1, and the vertical axis indicates the normalized transmittance (%) (no unit). The curve connecting the diamond points corresponds to the display panel described in the first embodiment, and the curve connecting the square points corresponds to the other display panel described in the first embodiment. Please refer to FIG. 6, FIG. 7 and FIG. Specifically, in these two display panels, the width of the distance W2 is about 4 μm, and the depth d of the concave groove of the protective layer is about 0.2 μm. The difference between the two display panels is that the width L1 / interval S1 of the branching projection pattern 144 of the display panel indicated by the curve connecting the diamond-shaped points is about 4 μm / 4 μm, and the width L2 / interval of the first branch electrode 124. S2 is about 4 μm / 2 μm. On the other hand, the width L1 / interval S1 of the branch projection pattern 144 of the display panel indicated by the curve connecting the square points is about 4 μm / 4 μm, and the width L2 / interval S2 of the first branch electrode 124 is about 4 μm / 4 μm. It is. As can be seen from FIG. 40, when the gap width W1 is about 0 μm <W1 ≦ 4 μm, the transmittance reaches about 85% or more, and when the gap width W1 is about 1 μm ≦ W1 ≦ 3 μm, the transmittance is If it reaches about 95% or more and the gap width W1 is about 2 μm, the transmittance can approach 100%. Incidentally, different transmittances are used for different display modes, but considering the light usage rate, it is appropriate that the transmittance is 85% or more.

  FIG. 41 is a schematic diagram showing the relationship between the transmittance of the display panel according to the first embodiment of the present invention and W2. As shown in FIG. 41, the horizontal axis indicates the distance (μm) of the distance W2, and the vertical axis indicates the normalized transmittance (%) (no unit). The curve connecting the triangular points corresponds to the display panel described in the first embodiment, and the curve connecting the square points corresponds to the other display panel described in the first embodiment. When W2 is greater than 0 (has a positive value “+”), the orthogonal projection (on the substrate) of the edge of the block-shaped electrode 122 indicates that the block-shaped protrusion pattern 142 is provided. When W2 is 0, it indicates that the edge of the block-shaped electrode 122 ′ is in contact with the side of the block-shaped protrusion pattern 142 but is provided in the concave groove 145. When W2 is smaller than 0 (has a negative value “−”), the edge of the block-shaped electrode 122 ′ is separated from the side of the block-shaped protrusion pattern 142 and is orthogonally projected (to the substrate) of the block-shaped electrode 122 ′. Indicates that it is not provided on the block-like protrusion pattern 142 but is provided in the groove 145 or on the branch protrusion pattern 144. Please refer to FIG. 6, FIG. 7 and FIG. Specifically, in these two display panels, the gap width W1 is about 2 μm, and the depth d of the groove of the protective layer is about 0.2 μm. The difference between the two display panels is that the width L1 / interval S1 of the branching projection pattern 144 of the display panel indicated by the curve connecting the triangular points is about 4 μm / 4 μm, and the width L2 / interval of the first branch electrode 124. S2 is about 4 μm / 2 μm. On the other hand, the width L1 / interval S1 of the branch projection pattern 144 of the display panel indicated by the curve connecting the square points is about 4 μm / 4 μm, and the width L2 / interval S2 of the first branch electrode 124 is about 4 μm / 4 μm. It is. As can be seen from FIG. 41, the gap width W1 is about 2 μm, which is the most preferable value (ie, has the maximum transmittance), and the distance W2 is 0.5 μm ≦ W2 ≦ 7 μm. The transmittance of the panel can reach about 98% or more. Incidentally, in consideration of manufacturing variations (for example, mask displacement (PEP shift)), if the selected distance W2 is within a range of about 1.5 μm, the transmittance of the display panel reaches at least about 98%. When W2 is 0 or less than 0 (has a negative value “−”), the transmittance of the display panel is 98% or less. As can be seen from FIG. 41, the selected distance W2 is preferably in the range of 2 μm ≦ W2 ≦ 5.5 μm, and most preferably 3 μm. W1 and W2 described in FIGS. 40 and 41 can be applied to the embodiments shown in FIGS. 12, 16, 20, and 24, for example. Further, the present embodiment has the effects of the above embodiments.

  FIG. 42 is a schematic diagram showing the relationship between the transmittance of the display panel and a and b according to the sixth embodiment of the present invention. As shown in FIG. 42, the horizontal axis represents distance (μm), and the vertical axis represents normalized transmittance (%) (no unit). The curve connecting the diamond points corresponds to the display panel described in the sixth embodiment, and the distance b is about 3 μm. The curve connecting the square points corresponds to the other display panel described in the sixth embodiment, and the distance a is about 2 μm. First, referring to a curve connecting the diamond-shaped points, when the distance a is about 0 μm <a <3 μm, the transmittance reaches about 85% or more, and when the distance a is about 2 μm, the transmittance is 100 % Can be close. In particular, since the pixel electrode of the present embodiment is a plurality of branch electrodes, it can be seen that the gap distance a between the two branch electrodes always satisfies the relationship of a ≠ 0 μm. Next, referring to a curve connecting square points, the transmittance can reach 85% or more when the distance b satisfies the relationship of about 0 μm <b ≦ 10 μm. Incidentally, in this embodiment, since the branch electrode of the pixel electrode extends to the branch projection pattern of the protective layer, it can be seen that the distance b satisfies the relationship of b ≠ 0 μm.

  FIG. 43 is a schematic diagram showing the relationship between the transmittance of the display panel and the mask displacement distance according to the sixth embodiment of the present invention. As shown in FIG. 43, the horizontal axis represents a mask displacement distance (PEP shift, μm), and the vertical axis represents normalized transmittance (%) (no unit). As shown in FIG. 43, the distance a of the display panel is about 2 μm, and the distance b is about 3 μm. In particular, in the manufacturing process, a mask shift of 1.5 μm may occur between the pixel electrode and the protective layer. As can be seen from FIG. 43, when the mask displacement distance is 1.5 μm, the variation in the transmittance of the display panel can be maintained within about 2% (that is, the transmittance> 98%). As described above, the selected distance b preferably satisfies the relationship of 1.5 μm ≦ b ≦ 10 μm, and most preferably about 1.5 μm.

  Since the protective layer in the present example has an uneven structure, the groove width c ≠ 0 μm. 44 is another schematic cross-sectional view along the line J-J ′ in FIG. 27. As shown in FIG. 44, in the manufacturing process, when the accuracy and uniformity of the photoresist and etching are insufficient, the protective layer in the groove 646 deteriorates and the surface roughness increases (see FIG. 44). May be caused by light leakage. Considering the above factors, it is preferable to satisfy c> 3 μm. Further, according to the experimental results in Table 1, in this example, when the depth d of the concave groove of the protective layer is about 0.2 μm, the ratio of L1> S1 or L1 / S1 increases and the dark state It can be seen that light leakage (L0 Leakage) is reduced. In other words, the smaller the recessed portion of the groove 646 of the protective layer, the less light leakage in the dark state, and the contrast can be improved. When the height of the branching protrusion pattern 642 of the protective layer is equal to the width of the groove 646, that is, (a + 2b) μm, the contrast can be maintained or improved. Therefore, the width c preferably satisfies the relationship of 3 μm <c ≦ (a + 2b) μm. The designs of a, b, and c described in FIGS. 42, 43, and 44 can be applied to the above-described embodiment shown in FIGS. 33 and 37, for example. Further, the present embodiment has the effects of the above embodiments.

  As described above, the pixel electrode of some embodiments of the present invention has a plurality of branch electrodes, and the protective layer has a plurality of branch protrusion patterns. The pixel electrode according to the present invention is configured by arranging the above-described branch electrode and branch projection pattern so as to intersect each other. Specifically, according to the pixel electrode of the present invention, it is possible to prevent the problem of unstable liquid crystal due to insufficient depth of the groove of the protective layer, and to improve the efficiency of the liquid crystal at the junction of the electrode. Can be improved. In addition, according to the pixel electrode of the present invention, it is possible to improve light leakage in the dark state due to the inclined side wall of the branching projection pattern of the protective layer, and to obtain a display panel having good transmittance and contrast. it can.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. Those skilled in the art can add some variation and coloration without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention is based on the description of the scope of claims.

10 substrate 12 pixel array layer 20 counter substrate 22 common electrode 30 display medium 100 pixel structure 120, 220, 320, 420, 520, 620, 720, 820, PE pixel electrode 122, 122 ′, 222, 322, 422, 522, 830 Block-shaped electrodes 122e, 124e, 222e, 222f, 322e, 324e, 342e, 422e, 442e, 522e, 542e, 622e, 646e, 722e, 746e, 722e, 822e, 848e Edges 124, 224, 324, 424, 524 First branch electrode 124a, 124a ′, 224a, 324a, 424a, 524a First first branch electrode 126, 226, 624, 724, 824 Main electrode 326 First main electrode 328 Second main electrode 128, 230, 330, 426 526 Second branch electrode 14 , 240, 340, 440, 540, 640, 740, 840 Protective layer 142, 242, 342, 442, 542 Block-like projection pattern 144, 244, 344, 444, 544, 642, 742, 842 Branching projection pattern 3441 First Branch projection pattern 3442 Second branch projection pattern 145 Groove 146, 246, 644, 744, 844 Main projection pattern 346 First main projection pattern 348 Second main projection pattern 160 Color filter layers 248, 846 Block-shaped patterns 228, 826 Outside Branch electrode 622, 722, 822 Branch electrode 626, 726, 828 Gap 646, 746 Groove 1000 Display panel 3241 First sub-branch electrode 3242 Second sub-branch electrode 4221, 5221 Sub-block-like electrode 4421, 5421 Sub-block-like projection pattern B Distance d Depth DL Data lines K1, K2, K3, K4, K5, K6, K7 Regions L1, L2, L3, L4, L5, L6, c Widths S1, S2, S3, S4, S5, S6 Distance SL Scan line T Active element W1 Gap width W2 Distance

Claims (28)

A substrate,
A counter substrate disposed above the substrate and having a common electrode disposed on a side facing the substrate;
A scan line and a data line formed on the substrate;
An active element formed on the substrate and connected to the scan line and the data line;
A pixel electrode electrically connected to the active element and having at least one block-like electrode and a plurality of first branch electrodes;
A protective layer provided below the pixel electrode and having at least one block-shaped protrusion pattern, a plurality of branch protrusion patterns, and a plurality of concave grooves;
The block electrodes of the pixel electrode are arranged so as to conformally cover the plurality of branching projection patterns of the protective layer and project by the plurality of branching projection patterns to form a plurality of second branch electrodes. And
The plurality of first branch electrodes of the pixel electrode are provided on the block-shaped protrusion pattern of the protective layer,
The edge of the block electrode of the pixel electrode extends to the block protrusion pattern of the protective layer,
A gap width W1 (0 μm <W1 ≦ 4 μm) between the orthogonal projection edge of the block-shaped electrode and the closest orthogonal projection edge of the first branch electrode;
2. A pixel structure having a distance W2 (2 μm ≦ W2 ≦ 5.5 μm) between an orthogonal projection edge of the block-shaped electrode and an orthogonal projection edge of the block-shaped protrusion pattern.   The pixel structure according to claim 1, wherein a depth of the plurality of concave grooves of the protective layer is 0.1 μm to 0.3 μm. The pixel electrode further includes a main electrode connected to the plurality of first branch electrodes,
The protective layer further includes a main protrusion pattern connected to the plurality of branch protrusion patterns,
The pixel structure according to claim 1, wherein the main electrode of the pixel electrode and the main protrusion pattern of the protective layer are arranged to intersect each other. The block electrodes of the pixel electrode are provided on both sides of the main electrode,
The pixel structure according to claim 3, wherein the block-shaped protrusion pattern of the protective layer is provided on both sides of the main protrusion pattern.   The pixel structure according to claim 3, wherein the pixel electrode further includes a plurality of outer branch electrodes connected to the block electrode. The protective layer further includes at least one block pattern,
The pixel structure according to claim 5, wherein the plurality of outer branch electrodes are arranged on the block pattern. The pixel electrode further includes a first main electrode and a second main electrode,
The plurality of first branch electrodes of the pixel electrode include a plurality of first sub-branch electrodes connected to the first main electrode and a plurality of second sub-branch electrodes connected to the second main electrode. Including
The block electrode is provided between the plurality of first sub-branch electrodes and the plurality of second sub-branch electrodes,
The protective layer further includes a first main protrusion pattern and a second main protrusion pattern,
The plurality of branch protrusion patterns of the protective layer include a plurality of first branch protrusion patterns connected to the first main protrusion pattern, and a plurality of second branch protrusion patterns connected to the second main protrusion pattern. Including
The block-shaped protrusion pattern includes a plurality of first sub-branch electrodes and a plurality of second sub-branches so that the block-shaped protrusion pattern overlaps the plurality of first sub-branch electrodes and the plurality of second sub-branch electrodes. The pixel structure according to claim 1, wherein the pixel structure is provided below the branch electrode. The block electrode of the pixel electrode includes a plurality of sub-block electrodes,
Between the two adjacent sub-block electrodes, at least one of the plurality of first branch electrodes has the first branch electrode,
The block-like protrusion pattern of the protective layer includes a plurality of sub-block-like protrusion patterns,
2. The pixel structure according to claim 1, wherein at least one of the plurality of branching protrusion patterns has the branching protrusion pattern between two adjacent sub-block-like protrusion patterns.   2. The pixel structure according to claim 1, wherein the W1 is 2 [mu] m, and the W2 is 3 [mu] m.   The pixel structure according to claim 1, further comprising a color filter layer formed on the substrate and provided below the protective layer. The width of the first branch electrode is in the range of 1 μm to 10 μm,
2. The pixel structure according to claim 1, wherein an interval between two adjacent first branch electrodes is in a range of 1 μm to 10 μm. The width of the plurality of branch projection patterns is in the range of 1 μm to 10 μm,
The pixel structure according to claim 1, wherein an interval between the plurality of branching protrusion patterns is in a range of 1 μm to 10 μm. A substrate,
A counter substrate disposed above the substrate and having a common electrode disposed on a side facing the substrate;
A scan line and a data line formed on the substrate;
An active element formed on the substrate and connected to the scan line and the data line;
A pixel electrode electrically connected to the active element and having a plurality of branch electrodes;
A protective layer provided below the pixel electrode and having a plurality of branching protrusion patterns,
If there is a slit between two adjacent branch electrodes, and the distance of the slit is a, the relationship 0 μm <a ≦ 3 μm is satisfied,
Having at least one groove between two adjacent branching protrusion patterns;
2. A pixel structure characterized by satisfying a relationship of 1.5 μm ≦ b ≦ 10 μm, where b is a distance between the orthogonal projection edge of the branch electrode and the orthogonal projection edge of the nearest groove.   The pixel structure according to claim 13, wherein a depth of the groove is in a range of 0.1 μm to 0.3 μm.   The pixel structure according to claim 13, wherein a relationship of 3 μm <c ≦ (a + 2b) μm is satisfied, where c is a width of the groove. Each branch electrode of the pixel electrode is disposed corresponding to one groove of the protective layer,
The pixel structure according to claim 13, wherein the branch electrode extends from the groove to the branch projection patterns on both sides adjacent to each other, and the slit is arranged to overlap the branch projection pattern. Each branch electrode of the pixel electrode is disposed corresponding to one branching protrusion pattern of the protective layer,
The pixel according to claim 13, wherein the branch electrode extends from the branch protrusion pattern into the grooves on both sides adjacent to each other, and the slit is disposed so as to overlap the grooves on both sides adjacent to each other. Construction. The pixel electrode further includes a main electrode,
The plurality of branch electrodes are connected to the main electrode and extend from the main electrode in a plurality of directions,
The protective layer further includes a main protrusion pattern,
The plurality of branching protrusion patterns are connected to the main protrusion pattern and extend in a plurality of directions from the main protrusion pattern,
The pixel structure according to claim 13, wherein the main electrode and the main protrusion pattern are arranged to overlap each other. The main electrode is formed in a cross shape,
The pixel structure of claim 18, wherein the main protrusion pattern is formed in a cross shape.   The pixel structure according to claim 18, wherein a width of the main electrode is larger than a width of the main protrusion pattern.   The pixel structure according to claim 18, wherein the pixel electrode further includes at least one block electrode and a plurality of outer branch electrodes connected to the block electrode. The protective layer further includes at least one block pattern,
The pixel structure according to claim 21, wherein the plurality of outer branch electrodes are disposed on the block pattern.   The pixel structure according to claim 13, wherein the a is 2 μm and the b is 1.5 μm.   The pixel structure according to claim 13, further comprising a color filter layer formed on the substrate and provided below the protective layer.   The pixel structure according to claim 13, wherein the branch electrode has a width in a range of 1 μm to 10 μm.   The pixel structure according to claim 13, wherein the branch protrusion pattern has a width in a range of 1 μm to 10 μm. A plurality of the pixel structures according to claim 1;
A pixel cell is constituted by at least three of the pixel structures,
The width or interval of the plurality of first branch electrodes of at least one of the pixel structures in the pixel cell is different from the width or interval of the plurality of first branch electrodes of other pixel structures in the pixel cell. Display panel. A plurality of the pixel structures according to claim 13,
A pixel cell is constituted by at least three of the pixel structures.
The width or interval of the plurality of branch electrodes of at least one of the pixel structures in the pixel cell is different from the width or interval of the plurality of branch electrodes of the other pixel structures in the pixel cell. .